Pinpoint Test B: One-Touch Integrated Start (OTIS) Does Not Operate Correctly
Starting System
Pinpoint Tests
Pinpoint Test B: One-Touch Integrated Start (OTIS) Does Not Operate Correctly
Refer to Wiring Diagram Set 20, Starting System for schematic and connector information. Diagrams By Number
Normal Operation
When the ignition switch is turned in the START position and released, the PCM receives a starter motor request signal. With the vehicle in PARK or NEUTRAL, power flows from the PCM to the starter motor relay through circuits 31S-BB16 (BK/RD) and 50-BB15 (GY/OG). A ground is supplied through circuit 31-BB16 (BK) from the PCM causing the starter motor relay coil to energize and the relay contacts close. This allows power from starter motor relay through circuit 50-BB12 (GY) to the starter solenoid. The solenoid is grounded at the starter motor. Energizing the starter solenoid will engage the starter drive into the ring gear and closes the solenoid contacts, allowing power directly from the battery through circuit 30-BB10 (RD) to the starter motor to start the engine. The customer is no longer in the loop after the initial crank request, the customer may release the key to the RUN/START position. The PCM will disengage the starter motor based on engine running (rpm threshold), a set crank time has been exceeded or the ignition switch has been turned to the OFF position.
This pinpoint test is intended to diagnose the following:
- Circuitry
- PCM
PINPOINT TEST B: OTIS DOES NOT OPERATE CORRECTLY
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B1 CHECK THE STATUS OF OTIS (OTS_STAT) PID
- Enter the following diagnostic mode on the scan tool: DataLogger - PCM.
- Monitor the OTS_STAT PID with the ignition switch in the RUN position.
- Is the One-Touch Integrated Start (OTIS) PID enabled?
Yes
GO to B2.
No
ENABLE OTIS. TEST the system for normal operation. If OTIS will not enable, INSTALL a new PCM. REFER to Computers and Control Systems. TEST the system for normal operation.
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B2 CHECK THE KEY POSITION FOR START INDICATED (START_KEY) PID
- Monitor the START_KEY PID with the ignition switch in the START position.
- Does the PID change from OFF to ON?
Yes
GO to B4.
No
GO to B3.
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B3 CHECK CIRCUIT 50-BB15A (GY/OG) FOR AN OPEN
- Disconnect: Start Diode.
- Disconnect: PCM C175B.
- Measure the resistance between the start diode cell, circuit 50-BB16 (GY/BK), harness side and PCM C175B-16, circuit 50-BB14 (GY/RD), harness side.
- Is the resistance less than 5 ohms?
Yes
INSTALL a new PCM. REFER to Computers and Control Systems. TEST the system for normal operation.
No
REPAIR circuit 50-BB15A (GY/OG). TEST the system for normal operation.
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B4 CHECK THE STARTER MOTOR CONTROL OUTPUT DETECTED (SMC_MON) PID
- Enter the following diagnostic mode on the scan tool: DataLogger - PCM.
- Monitor the SMC_MON PID with the ignition switch in the START position.
- Does the PID change from OFF to ON?
Yes
GO to B6.
No
GO to B5.
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B5 CHECK THE CIRCUIT BETWEEN THE BJB AND THE PCM
- Connect: Start Diode.
- Disconnect: Starter Motor Relay.
- Measure the resistance between the starter motor relay pin 1, circuit 31S-BB16 (BK/RD), harness side and C175B-37, circuit 50-BB15A (GY/OG), harness side.
- Is the resistance less than 5 ohms?
Yes
INSTALL a new PCM. REFER to Computers and Control Systems. TEST the system for normal operation.
No
REPAIR circuit 31S-BB16 (BK/RD) or 50-BB15A (GY/OG). TEST the system for normal operation.
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B6 CHECK THE STARTER MOTOR RELAY ENABLE (STRT_RLY) PID
- Enter the following diagnostic mode on the scan tool: DataLogger - PCM.
- Monitor the STRT_RLY PID with the ignition switch in the START position.
- Does the PID change from DISABLED to ENABLED?
Yes
REPAIR circuit 31-BB16 (BK). TEST the system for normal operation.
No
INSTALL a new PCM. REFER to Computers and Control Systems. TEST the system for normal operation.
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